The reason is the fact that rules are evaluated strictly left to right. Once it got to the OR and that which was before the OR was true, that was enough for the rule to be true. (see the documentation here: Rule Machine® Introduction):
It's easy to work around this. One way would be to put all of your AND parts before any OR part. Another way would be to use parens to group parts together (select complex rule for parens to be available).
